Pencil sharpener

ABSTRACT

The present invention relates to an improved pencil sharpener which is constructed from sheet metal material suitable for punching and forming in high speed machine press, such as a punch press. In this manner an economical holder is manufactured for the used razor blades, since the holder has pressure means suitable for holding a blade in such a position that the edge assumes the correct angle with respect to the hollow cone in which the end of the pencil is turned. The blade holding means may be varied insofar as the dimensions and shapes are concerned in order to be able to retain razor blades of the more normally used types. Under all circumstances, whatever be the type of razor blades used, the cutting edge should always assume the correct position with respect to a slot provided along a generatrix of the hollow cone.

United States Patent 1 1 Nochea June '26, 1973 PENCIL SHARPENER Primary Examiner0thell M. Simpson Assistant Examiner-Mark S. Hicks [75] lnvemor' x1 3? 53 gunfire: Nochn Attorney-Mason, Kolehmainen, Rathburn & Wyss [73] Assignee: Jose Materno Gutierrez Y. Zerquera, [57] ABSTRACT New York The present invention relates to an improved pencil [22] Filed: June 15, 1971 sharpener which is constructed from sheet metal material suitable for punching and forming in high speed [21] Appl. No.. 153,193 machine press, such as a punch press. In this manner an economical holder is manufactured for the used razor 52 US. Cl. l45/3.61 blades, since the holder has Pressure means suitable f [51] Int. Cl B26b 3/00 hclding a blade in u a pos t o that the edge assumes [5 8] Field of Search 14513.1, 3.2, 3.3, he correct angle with respect to the hollow cone in 145/331, 3.32, 3.4, 3.5, 3.6, 3.61, 3.7, 3.8, which the end ofthe pencil is turned. The blade holding 3.9; 269/1, 15, 16 means may be varied insofar as the dimensions and shapes are concerned in order to be able to retain razor [56] Ref r ce Cit d blades of the more normally used types. Under all cir-' UNITED STATES PATENTS cumstances, whatever be the type of razor blades used, 2,096,762 10 1937 Quinby 145/331 the cuttmg edge shuld always assume the tion with respect to a slot provided along a generatrix of the hollow cone.

5 Claims, 5 Drawing Figures PENCIL SHARPENER Many devices are known for cutting and sharpening the points of pencils, but all these devices have the great inconvenience of requiring special blades which when they lose their edge involve loss of the usefulness of the device as a whole. Moreover, in the devices which are now found on the market, the cost corresponding to the blade represents a very significant percentage of the total value. Therefore, there is no important saving for the user in the replacement of the worn blades.

The improved pencil sharpener which is described herein has the advantage that, by this means, the blade no longer presents a problem; now when the blade is dulled, it is replaced by a used razor blade,'which is still suitable for cutting wood and graphite, the materials of a pencil.

To such an end, the pencil sharpener which is reduced to practice is constructed from sheet metal material suitable for punching and forming in high speed machine press, such as a punch press. In this manner an economical holder is manufactured for the used razor blades, since the holder has pressuremeans suitable for holding a blade in such a position that the edge assumes the correct angle with respect to the hollow cone in which the end of the pencil is turned. The bladeholding means may be varied insofar as the dimensions and shapes are concerned in order to be able to retain razor blades of the more normally used types. Under all circumstances, whatever be the type ofrazor blades used, the cutting edge should always assume the correct position with respect to a slot provided along a generatrix of the hollow cone.

For a better understanding of the object of the invention and solely as an example, a set of drawings is provided in which:

FIG. 1 represents the holder-box in the flat before forming it.

FIG. 2 represents a conventional razor blade.

FIG. 3 represents the blade position adjusting device in the flat before forming it.

FIG. 4 represents the adjusting screw.

FIG. 5 represents a view of the pencil sharpener assembly.

In the illustrations and the following description, the component elements and their main parts have been indicated in accordance with the following nomenclature:

l. Holder-box 2. Upper plane 2a. Slots 3. Lower plane 30. Hole 4. Rear side 5. Lateral sides 5a. Tabs 6. Inner bending lines 7. Rectangular extension 8. Hole 9. Pressure screw 10. End-relieved slot 11. Partial cut 12. Keyhole slot 13. Triangular tab of the free edge 14. Hollow cone 15. Blade 16. Lateral and front lids 17. Bend 18. Rear extension 18a. Notch 19. Blade adjuster 20. Slotted cut 21. Tab

Referring to the figures, we may see that the holderbox 1 consists of an upper plane 2, a lower plane 3, a rear side 4 and two lateral sides 5, all of which are rectangular and set off by the inner bending lines 6, by which, and with the aid of the tabs 5a of the edges of the lateral sides 5, said tabs engage with the slots 2a of the upper plane 2, and the parallele-piped-shaped form of the holder-box 1 is attained, a view of which may be seen in FIG. 5 with the front side lacking.

The lower plane 3 has as a part of it along the center of its unattached edge a rectangular extension 7, with a hole 8; When the rectangular extension 7 is folded along the inner bending line 6 against the lower plane 3, the hole 8 of the rectangular extension 7 is superposed above the hole 30 of the lower plane 3 in such a way as to provide a double thickness of sheet material thus permitting the formation of threads for holding the pressure screw 9.

At the same time, the upper plane 2 contains in symmetrically lateral locations the two end-relieved slots 10, whose ends are beaded through a reduced dimension along a line joining the corresponding ends of the slots 10 and the partial cut 11, the latter form ing a pocket in the upper plane 2 and a corresponding lid of which extends the surface of the narrow strip formed along the free edge of the said upper plane 2, said lid carryingthe keyhole slot 12 of such proper form that its edge abuts the edge of the triangular tab 13 which, simultaneously with the above-described forming steps,

, is curved and rolled to form the hollow cone 14 (FIG.

The upper plane 2 area between the end relieved slots 10 thus comprises the receiver, in which the blade 15 is placed after the inner bending lines 6 are formed at right angles to produce the side and forward portions of the lids 16. The rear edge of the blade 15 abuts against the bend 17 formed by bending in a zig-zag the rear extension 18 of the blade adjuster 19 (FIG. 3), which presents the same shape and size as'the blade 15 and together with which is placed in the receiving means, formed within the interior surface of the upper plane 2 and receiving, in turn, the'thrust of the end of the pressure screw- 9.

As we may see in FIGS. 1 and 5, the rear extension 18 passes from the inside to the outside through the slotted cut 20 in the upper plane 2, where .it is held against the plane and fixed by means of a tab 21, which is formed by a partial cut made in the plane 2 and bent over the notch 18a, thus achieving centering for the correct positioning of the parts. This assembly can have slight variations imposed mainly by the different shapes or types of razor blades to be used and for which the pencil sharpener as described is prepared. Among these variations we may mention the substitution of the rear extension 18, located in the center of the edge of the blade adjuster 19, by two projecting tabs conveniently separated along the same edge.

When the end of apencil is inserted and made to turn within the hollow cone l4,*the cutting edge of the blade 15 cuts a time shavingwhich'passes through the keyhole slot 12 and, if the position of the pencil sharpener is correct, this shaving is continuously deposited in the interior of the holder-box l, whence it is dumped into the waste receptacle, after the operation is finished, through the open space left by the missing front side.

The combination of size, shape and material particularly referred to in regard to each one of the elements which comprise the whole of the pencil sharpener may be varied without any alteration in the essence of the objective described in the above description, which will be taken in its broadest sense and not as any limitation of the means for accomplishing the embodiment.

What is claimed is:

1. An improved pencil sharpener, of a type which permits the utilization of used razor blades, formed from a developed flat blank into a parallelepipedshaped holder-box having an upper. plane, a lower plane, a rear side and two lateral sides, all of which are rectangular and bounded by inward bending lines, a pair of tabs extending from the edges of the lateral sides and engaging two corresponding slots in the upper plane, said holder box being open at the front side in order to permit the exit of the shavings, which, at the time the-point of the pencil is sharpened, have been deposited within the holder-box.

2. An improved pencil sharpener as defined in claim 1, wherein the lower plane of the holder-box, in the central portion of its free edge, has a rectangular extension provided with a hole which is folded over against the surface of said plane, said hole being superposed above another hole in said plane creating an area of double thickness of sheet material permitting the formation of several threads for assemblying a pressure screw.

3. An improved pencil sharpener as defined in claim 1, wherein the upper plane of the holder-box has, in

symmetrically lateral positions, two end-relieved slots whose ends are beaded along a reduced dimension and in line with a partial cut, the latter forming a pocket in the upper plane and a corresponding lid of which extends the surface of the narrow strip formed along the free edge of said upper plane, a triangular tab extending from the free edge of the upper plane, said lid carrying a keyhole slot of such proper form that its edge abuts an edge of the triangular tab, which simultaneously with the above-described forming steps, is curved or rolled to form a hollow cone in which the point of the pencil is sharpened.

4. An improved pencil sharpener as defined in claim 3, characterized in that it includes in the area of the upper plane between the end-relieved slots, a receiver for retaining a razor blade, said receiver having the proper dimensions, therefore when a side and aforward lid accommodating said blade are bent at right angles along corresponding bending lines, the rear edge of said blade abutting against a bend formed by folding in a zig-zag manner the rear extension of a blade adjuster having the same shapes and sizes as the blade, and together with which is placed in said receiver, said receiver being formed within the interior surfaceof said upper plane, and a pressure screw is threaded into the lower plane and bearing against said receiver.

5. An improved pencil sharpener as defined in claim 4, characterized in that the rear extension plane of said blade adjuster passes from the inside to the outside through a slotted cut within the upper plane of the holder-box, against which saidrear extension plane is retained by means of a tab, which is formed by a partial cut made in said plane and which is folded over a notch, by which means the parts are centered and correctly positioned. 

1. An impRoved pencil sharpener, of a type which permits the utilization of used razor blades, formed from a developed flat blank into a parallelepiped-shaped holder-box having an upper plane, a lower plane, a rear side and two lateral sides, all of which are rectangular and bounded by inward bending lines, a pair of tabs extending from the edges of the lateral sides and engaging two corresponding slots in the upper plane, said holder box being open at the front side in order to permit the exit of the shavings, which, at the time the point of the pencil is sharpened, have been deposited within the holder-box.
 2. An improved pencil sharpener as defined in claim 1, wherein the lower plane of the holder-box, in the central portion of its free edge, has a rectangular extension provided with a hole which is folded over against the surface of said plane, said hole being superposed above another hole in said plane creating an area of double thickness of sheet material permitting the formation of several threads for assemblying a pressure screw.
 3. An improved pencil sharpener as defined in claim 1, wherein the upper plane of the holder-box has, in symmetrically lateral positions, two end-relieved slots whose ends are beaded along a reduced dimension and in line with a partial cut, the latter forming a pocket in the upper plane and a corresponding lid of which extends the surface of the narrow strip formed along the free edge of said upper plane, a triangular tab extending from the free edge of the upper plane, said lid carrying a keyhole slot of such proper form that its edge abuts an edge of the triangular tab, which simultaneously with the above-described forming steps, is curved or rolled to form a hollow cone in which the point of the pencil is sharpened.
 4. An improved pencil sharpener as defined in claim 3, characterized in that it includes in the area of the upper plane between the end-relieved slots, a receiver for retaining a razor blade, said receiver having the proper dimensions, therefore when a side and a forward lid accommodating said blade are bent at right angles along corresponding bending lines, the rear edge of said blade abutting against a bend formed by folding in a zig-zag manner the rear extension of a blade adjuster having the same shapes and sizes as the blade, and together with which is placed in said receiver, said receiver being formed within the interior surface of said upper plane, and a pressure screw is threaded into the lower plane and bearing against said receiver.
 5. An improved pencil sharpener as defined in claim 4, characterized in that the rear extension plane of said blade adjuster passes from the inside to the outside through a slotted cut within the upper plane of the holder-box, against which said rear extension plane is retained by means of a tab, which is formed by a partial cut made in said plane and which is folded over a notch, by which means the parts are centered and correctly positioned. 